Sanding device



B. PETROWSKY SANDING DEVICE Nov. 29, 1955 Filed Nov. 5, 1953 I INVENTOR 772m Zerowsf ATTORNEYS United States Patent @ffice 2,724,936 Patented Nov. 29, 1955 SANDING DEVICE Benjamin Petrowsky, Brooklyn, N. Y.

Application November 5, 1953, Serial No. 390,349

s claims. (ci. s11s7) This invention relates to abrading devices and more particularly to a hand-held sanding device particularly adapted to sanding the finishes of vehicles and the like.

In the performance of abrading or sandpapering operations it has been found extremely desirable to provide a supporting block for the sandpaper, emery cloth, or the like, in order to eliminate hand fatigue and to provide for etiicient use of the abrasive means. Various types of supporting blocks have been proffered with all of them more or less comprising rigid material at the core. These devices failed to satisfactorily eliminate hand strain because of the hardness of the block against which the hand must press in operating the device. In addition they were not able to be bent in order to conform to the contours of various devices to be abraded, such as automobile bodies and the like. Thus they were extremely difficult to use on bodies that were curved, grooved, or otherwise rounded.

Itis an object of the present invention to provide means for supporting a strip of abrading material, which means is soft and flexible to eliminate hand strain.

It is a still further object of this invention to provide supporting means for a strip of abrasive material constructed in such fashion that the abrasive material will be usable for a long period of time.

A feature of this invention is the provision of a supporting block for sandpaper and the like wherein when the sandpaper is worn out, it may be easily and quickly replaced.

Still another feature of the present invention is the provision of such a supporting block which while accomplishing all the desired results set forth, nevertheless is economical to manufacture and construct.

With these objects and features in mind, in addition to others as hereinafter set forth, the invention consists of novel features of construction as hereinafter illustrated in the accompanying drawings, in which Figure l is a side elevation partly in section showing a preferred embodiment of the invention;

Fig. 2 is a vertical section taken along lines 2--2 of Fig. l;

Fig. 3 is a top View of the clamping head portion of the device of my invention;

Fig. 4 is a perspective view of the clamping head portion with the bar in vertical position; and

Fig. 5 is a perspective view of a piece of sandpaper used with my invention.

Referring to the drawings, I have provided a socket-like head portion 11 adapted to receive one end of a removable block 12. The block comprises pliable resilient material as, for example, soft rubber or the like, and is inserted into the socket-like support as shown. The dimensions of the interior of the socket are smaller than the external dimensions of the removable resilient block whereby when the block and head are assembled a frictional engagement is obtained between said socket and one end of the resilient block.

The socket 11 is provided at the top thereof with a pair of button-like elements 13 and 14 having shoulders 15 and 16. A clamping bar 17 is carried by the socket-like head portion 11 and is normally urged by a spring 18 into vertical position, as shown in Fig. 4. The bar is provided with keyhole slots 19 and 20 which, when the bar is urged into horizontal position, receive the button-like elements 13 and 14. In its horizontal position lengthwise movement of the bar to a limited degree is permitted by slots 21 provided in the bent ears 22, the said slots accommodating a pivot pin 23 secured to the socket-like head portion 11.

To lock the bar in horizontal position, it is slid lengthwise to a position where the smaller portions of the keyhole slots 19 and 20 accommodate the respective Shanks of the button-like elements 13 and 14 whereby upward opening movement is prevented by the engagement of these portions of the keyhole slots with the shoulders 14 and 15. The bar is provided with a flange 24 and it will be understood that opposite lengthwise movement of the bar by pushing the same by the fiange to a position where the button-like elements are located in the larger opening of the keyhole slots will permit the bar to spring up into vertical position for the purposes hereinafter set forth.

In assembling the sanding device of my invention the block l2 is inserted in the socket-like head portion 11 with the bar in its vertical position. One end 25 of a piece of sandpaper 26 preferably having openings 27 and 27 and 28 and 28', as shown in Fig. 5, is placed over the top of the head portion with the openings 27 and 27 receiving the respective button-like elements 13 and 14. The sandpaper` is then Wrapped around the resilient block 12 and the other end 29 of the sandpaper is placed over the aforesaid end 25, and the top of the head portion with the openings 28 and 2S receiving the respective button-like elements 13 and 14. It will be understood that it is preferable to have the sandpaper or other abrasive means wrapped tightly around the resilient block. To this end the block should be folded over upon itself or otherwise compressed prior to wrapping the sandpaper around the same. The sandpaper is then wrapped around the block while it is in its folded over or compressed position and when the other end 29 is placed over the top of the head portion, as above described, the block is released and the expansion of the block against the sandpaper will cause the sandpaper to be tightly wrapped therearound. Thereafter the clamping bar 17 is urged downwardly into horizontal position over the ends 25 and 29 of the sandpaper whereby the keyhole slots 19 and 2t) receive the buttonlike elements 13 and 14. The bar 17 is then slid lengthwise to a position where the smaller portions of the keyhole slots 18 and 19 accommodate the respective shoulders 15 and 16 of the button-like elements whereby upward opening movement of the bar is prevented by the engagement of the aforesaid portions of the keyhole slots with the shoulders 15 and 16 of the button-like elements. It will be understood that the unit may be disassembled for the replacement of the sandpaper by an opposite lengthwise movement of the bar 17 whereupon the bar will be urged by the spring 13 into vertical position and the sandpaper may be easily removed and replaced.

It has been found that because the block 12 is composed entirely of resilient material, the sandpaper may be used for a longer period of time.

Referring particularly to Fig. l, it is often found desirable to apply water to the device to be sanded in conjunction with the use of the sandpaper. For this purpose I have provided a tubular core Ell throughout the center of the resilient block 12 and through which Water may pass onto the device to be sanded. T he bore is prevented from collapsing by substantially rigid means, as for example a spring 31 inserted therethrough. In order to make connection of the device to means for obtaining water in a steady iiow, I have provided a telescopic connector 32 on the clamping bar and socket head. The upper end 33 of the connector is, as will be readily understood, connectable to water supply means, as for example, a rubber hose or the like through which water is supplied.v The water will thereupon pass out through the opening 34 and onto the device to be sanded in conjunction with the sanding operation.

A modified form of my invention is shown in Fig. 2 in which a covering of canvas 35 or similar material is provided over one side of the sanding device in order that the hand of the operator need not come into contact with the rough sandpaper or abrasive means. In assembling the canvas to the device, one end of the canvas 36 is placed over the button-like elements after the assembly of the sandpaper around the resilient block as aforesaid and prior to urging the bar 17 into horizontal position. The bar is thereafter urged downwardly into horizontal position in the usual fashion and locked into position in the manner hereinbefore described. The upper portion of the canvas will thereupon be clamped between the clamping bar 17 and the sandpaper.

Having thus described my invention, it is to be understood that variations and modifications of the details set forth may be made without departing from the scope thereof.

I claim:

l. A hand-held sanding device comprising a flexible core of resilient material adapted to deform under working pressures and resume its original shape when said pressures are removed; a socket head accommodating one end of said core having button-like means thereon; a sheet of abrasive material overlying the core and having openings at its ends adapted to fold over said socket head and receive said button-like elements for securing the abrasive material in operating position.

2. A hand-held sanding device comprising a flexible core of resilient material adapted to deform under working pressures and resume its original shape when said pressures are removed; a socket head accommodating one end of said core having button-like means thereon; clamping means carried by said socket head provided with openings adapted to receive and engage the button-like elements and disposed over the ends of said abrasive material for securing the ends of the abrasive material to the socket head and around the core.

3. A hand-held sanding device comprising a liexible core of resilient material adapted to deform under Working pressures and resume its original shape when said pressures are removed; a socket head accommodating one end of said core having button-like means thereon; said button-like means being provided with shoulders; a clamping bar carried by said socket head; a spring carried by said clamping bar urging said bar into vertical position; pivot means secured to the socket head for pivoting the bar into horizontal position; a pair of ears on said clamping bar provided with slots, said pivot means extending through said slots and said bar being provided with keyhole slots adapted to receive and engage said button-like means; a sheet of abrasive material overlying the core having openings at the ends thereof adapted to fold over said socket-like head and receive said button-like elements; said clamping bar disposed over the ends of said abrasive material for clamping the abrasive material to the socket head.

4. The invention as dened in claim 3 in which the slots in the ears of the clamping bar permit lengthwise movement of the clamping bar in its horizontal position to a limited degree whereby the'smaller portions of the keyhole slots engage the shoulders of the button-like elements to prevent upward outward movement of the bar.

5. A hand-held abrading device comprising a flexible core consisting solely of resilient yieldable material adapted to deform under working pressures and resume its original shape when said pressures are removed; a sheet of abrasive material overlying the outside of the core; and releasable means for clamping the ends of the abrasive sheet to the core, to secure the sheet in operative position around the core; a bore through said core for the passage of water; and substantially rigid means comprising a spring carried by said bore to prevent collapse thereof.

6. A hand-held sanding device comprising a flexible core of resilient material adapted to deforrn under working pressures and resume its original shape when said pressures are removed; button-like means mounted on one end of the core; a sheet of abrasive material overlying the core and having openings at its ends adapted to receive said button-like means for securing the abrasive material in operating position.

7. A hand-held sanding device comprising a flexible core consisting solely of resilient yieldable material adapted to be formed under working pressures and resume its original shape when said pressures are removed; button-like means mounted on one end of the core; a sheet of abrasive material overlying the core and having openings at its ends adapted to receive said button-like means for securing the abrasive material in operative position around the core; and means providing a channel through said core for the passage of water.

8. A hand-held sanding device comprising a flexible core of resilient material adapted to deform under working pressures and resume its original shape when said pressures are removed; button-like means mounted on one end of the core; a sheet of abrasive material overlying the core and having openings at its ends adapted to receive said button-like means for securing the abrasive material in operating position; a bore through said core for the passage of water; and substantially rigid means carried by said bore to prevent collapse thereof.

References Cited in the le of this patent UNITED STATES PATENTS 271,222 Cottin Jan. 30, 1883 1,562,414 McKnight Nov. 17, 1925 1,599,906 McKnight Sept. 14, 1926 1,862,135 Buey June 7, 1932 2,112,593 Campbell Mar. 29, 1938 2,446,183 Larson Aug. 3, 1948 2,547,837 Robbins Apr. 3, 1951 

